Clinical Utility of Next-generation Sequencing in the Aetiological Diagnosis of Sensorineural Hearing Loss in a Childhood Hearing Loss Unit

Abstract

IntroductionSensorineural hearing loss (SNL) is the most prevalent sensory deficit in our environment. The next generation genomic sequencing (NGS) allows to obtain an etiological diagnosis in a high percentage of patients. Our pilot study shows the results of the systematic application of NGS in a Childhood Hearing Loss Unit, as well as its implications in the clinical management of patients and their families. Material and methodWe included 27 patients diagnosed with SNH between 2014 and 2017, in which an environmental cause was ruled out. The genetic test consisted of a panel of genes analyzed by NGS (OTOgenics™ panel). This panel has been designed to include genes associated with sensorineural or mixed hearing loss, early onset or late, syndromic and non-syndromic, regardless of their inheritance pattern. ResultsA genetic diagnosis was obtained in 56% (15/27) of the patients (62% in the case of bilateral HNS). 5/27 (19%) presented pathogenic variants in the GJB2 gene and the rest variants pathogenic and/or probably pathogenic in other genes associated with isolated HNS (PR2 × 2, TECTA and STRC), with syndromic HNS (CHD7, GATA3, COL4A5, MITF and SOX10) or with syndromic and non-syndromic HNS (BSND, ACTG1 and CDH23). DiscussionThe etiological diagnosis of SNL is a challenge in clinical practice. Our series demonstrates that it is possible to implement genetic diagnosis in the daily routine and that this information has prognostic and therapeutic implications.